Runout effects in milling: Surface finish, surface location error, and stability

This paper investigates the effect of milling cutter teeth runout on surface topography, surface location error, and stability in end milling. Runout remains an important issue in machining because commercially-available cutter bodies often exhibit significant variation in the teeth/insert radial locations; therefore, the chip load on the individual cutting teeth varies periodically. This varying chip load influences the machining process and can lead to premature failure of the cutting edges. The effect of runout on cutting force and surface finish for proportional and non-proportional tooth spacing is isolated here by completing experiments on a precision milling machine with 0.1 μm positioning repeatability and 0.02 μm spindle error motion. Experimental tests are completed with different amounts of radial runout and the results are compared with a comprehensive time-domain simulation. After verification, the simulation is used to explore the relationships between runout, surface finish, stability, and surface location error. A new instability that occurs when harmonics of the runout frequency coincide with the dominant system natural frequency is identified.

[1]  Dong-Woo Cho,et al.  Accurate 3-D cutting force prediction using cutting condition independent coefficients in end milling , 2001 .

[2]  Dong-Woo Cho,et al.  Development of a virtual machining system, part 1: approximation of the size effect for cutting force prediction , 2002 .

[3]  Hsi-Yung Feng,et al.  The prediction of cutting forces in the ball-end milling process—II. Cut geometry analysis and model verification , 1994 .

[4]  S. Smith,et al.  An Overview of Modeling and Simulation of the Milling Process , 1991 .

[5]  Steven Y. Liang,et al.  Milling force convolution modeling for identification of cutter axis offset , 1994 .

[6]  Tae Jo Ko,et al.  Optimization of feedrate in a face milling operation using a surface roughness model , 2001 .

[7]  Richard E. DeVor,et al.  The effect of runout on cutting geometry and forces in end milling , 1983 .

[8]  Ismail Lazoglu,et al.  Sculpture surface machining: a generalized model of ball-end milling force system , 2003 .

[9]  Yusuf Altintas,et al.  An Improved Time Domain Simulation for Dynamic Milling at Small Radial Immersions , 2003 .

[10]  Yusuf Altintas,et al.  Analytical Prediction of Stability Lobes in Milling , 1995 .

[11]  Steven Y. Liang,et al.  Runout rejection in end milling through two-dimensional repetitive force control , 1995 .

[12]  Martin B.G. Jun,et al.  Cutting Mechanisms and Their Influence on Dynamic Forces, Vibrations and Stability in Micro-Endmilling , 2004 .

[13]  Satoshi Sakamoto,et al.  Prediction of cutting forces and machining error in ball end milling of curved surfaces -II experimental verification , 2002 .

[14]  Jon R. Pratt,et al.  Stability Prediction for Low Radial Immersion Milling , 2002 .

[15]  Dong-Woo Cho,et al.  DEVELOPMENT OF A VIRTUAL MACHINING SYSTEM FOR ESTIMATION OF CUTTING PERFORMANCE , 2001 .

[16]  Erhan Budak,et al.  An Analytical Design Method for Milling Cutters With Nonconstant Pitch to Increase Stability, Part 2: Application , 2003 .

[17]  Shivakumar Raman,et al.  A review of: “Manufacturing Processes and Equipment” J. TLUSTY Prentice Hall, Upper Saddle River, NJ ISBN 0-201-49865-0 , 2002 .

[18]  Yusuf Altintas,et al.  Manufacturing Automation: Metal Cutting Mechanics, Machine Tool Vibrations, and CNC Design , 2000 .

[19]  Ching-Chih Tai,et al.  THE PREDICTION OF CUTTING FORCES IN THE BALL-END MILLING PROCESS , 1995 .

[20]  Tae Jo Ko,et al.  A dynamic surface roughness model for face milling , 1997 .

[21]  Jiří Tlustý,et al.  Manufacturing processes and equipment , 1999 .

[22]  Erhan Budak,et al.  An analytical design method for milling cutters with nonconstant pitch to increase stability, Part I: Theory , 2003 .

[23]  Yusuf Altintas,et al.  Mechanics of boring processes—Part I , 2003 .

[24]  Satoshi Sakamoto,et al.  Prediction of cutting forces and machining error in ball end milling of curved surfaces -I theoretical analysis , 2001 .

[25]  Philip K. Chan,et al.  In-process detection and suppression of chatter in milling , 1992 .

[26]  Andrew Y. C. Nee,et al.  Theoretical modelling and simulation of cutting forces in face milling with cutter runout , 1999 .

[27]  Hsi-Yung Feng,et al.  The prediction of cutting forces in the ball-end milling process—I. Model formulation and model building procedure , 1994 .

[28]  Richard E. DeVor,et al.  Use of radial forces for fault detection in tapping , 2002 .

[29]  Steven Y. Liang,et al.  In-process monitoring of end milling cutter runout , 1997 .

[30]  Junz Jiunn-jyh Wang,et al.  Identification of cutter offset in end milling without a prior knowledge of cutting coefficients , 2003 .

[31]  René Mayer,et al.  Surface shape prediction in high speed milling , 2004 .

[32]  John W. Sutherland,et al.  The Role of Flank Face Interference in Improving the Accuracy of Dynamic Force Predictions in Peripheral Milling , 1999 .

[33]  T. I. El-Wardany,et al.  A multi-sensor strategy for tool failure detection in milling , 1995 .